Re: [PATCH 0/7] selftests/ftrace: Some improvements of ftracetest

[Shuah Khan]

On 06/08/2017 03:39 PM, Steven Rostedt wrote:
> On Thu, 8 Jun 2017 15:33:39 -0600
> Shuah Khan <shuahkh@xxxxxxxxxxxxxxx> wrote:
> 
> 
>>> Note, when a bug is found, we do add the reproducer to ftracetest. So
>>> depending on whether you have the latest stable, or the stable has a
>>> fix, ftracetest can cause the machine to crash on older releases.  
>>
>> Yeah - that could be problem, I would worry more if ftracetest can be run
>> as a non-root user. As ftracetest is intrusive in nature just like the timer
>> tests, we could say user needs to be aware.
>>
>> If the outcome isn't desirable, we could run ftracetest conditionally as
>> a last resort. I think it is important for it to be run as part of kselftest
>> suite run.
> 
> Well, I wouldn't worry too much. It shouldn't do any damage. And
> anything that can trigger a bug in previous kernels should be
> backported as well to the stable releases. Everyone runs the latest
> stable kernels, right?
> 
> Also, did you see my reply about having the right config? You have
> HIST_TRIGGERS undefined but yet the histogram trigger tests all pass in
> your report.

I did see that one. Didn't get a chance to look at that yet. Do you expect
the tests to be skipped in this case? Could it be that tests aren't run?
I will look at this and let you know what I find on my test system.

> 
> One more thing, is this 100% reproducible. That is, does it always fail?
> 
Failed the two times I tried.

thanks,
-- Shuah